Please help A water tank casts a shadow 21 m long. A tree of height 9.5 m casts
a shadow 8 m long at the same time. The lengths of the shadows are
directly proprotional to their heights. Find the height of the tank.

Step-by-step explanation:

→ Write out the direct proportion equation

y = kx

→ Substitute in x = 21 and y = 8

8 = 21k

→ Divide both sides by 8 to isolate k

k = 2.625

→ Substitute back into original equation

y = 2.625k

→ Substitute 9.5 for k

y = 2.625 × 9.5 ⇔ 24.9375

24.9 meters to the nearest tenth.

Step-by-step explanation:

We have 2 similar triangles here so:

21/8 = h/9.5

h = 21* 9.5 / 8

= 24.94 m = the height of the tank.